Last year we also wanted to drive Torsby around 16 O'Clock the day before and the road was already blocked. It's clear that the organizers don't want any trouble caused by spectators being stuck the night before the stages. I don't know if there are passes for single stages and how much they are? That may be an option if you are not doing a lot of stages. Also I don't think it's possible to do a lot of stages with a camper van. Keep in mind that distances between stages are always much bigger and take more time than they look on the map...